Which method is not advisable when the humidity outside is higher than inside?

Creating slight positive pressurization in a scenario where the outside humidity is higher than the inside is not advisable because it can lead to an influx of humid air into the interior space. Positive pressurization allows outside air to enter the building, which can bring elevated moisture levels indoors and potentially exacerbate mold growth or water damage issues. In environments where humidity is a concern, the goal is often to keep the drier, conditioned air inside and prevent the more humid outside air from entering.

Maintaining neutral air pressure would ensure that there is no airflow from outside to inside, helping to keep the humidity levels consistent. Similarly, implementing negative pressurization could effectively draw air out of the space, which may help in controlling indoor air quality and humidity levels. Using mechanical ventilation systems, when properly controlled, can help to manage humidity by filtering and dehumidifying the incoming air before it enters the living space. Hence, the other methods can effectively limit the impact of outside humidity, while slight positive pressurization counteracts that goal.